Chevron, the second-biggest U.S. oil company in market value behind Exxon Mobil Corp., has been working to increase its oil-and-gas production. But oil prices have plummeted in recent months amid an oversupply, just as its drive begins to show results.

The company has said it would trim spending and stop buying back its shares as the collapse in oil prices has wiped billions of dollars from its cash flow.

Chevron's profits are better insulated than most oil producers because it also makes money from refining the fuel into gasoline and diesel. The lower-cost crude has helped its refinery businesses improve profit margins.

In the latest quarter, refining, marketing and chemical operations, or downstream, earnings rose to $1.42 billion from $710 million.

Meanwhile, earnings from exploration and production, or the upstream segment, fell to $1.56 billion from $4.31 billion.

In all, Chevron reported earnings of $2.57 billion, or $1.37 a share, down from $4.51 billion, or $2.36 a share, a year earlier.

Revenue dropped to $34.56 billion.

Analysts polled by Thomson Reuters had forecast earnings of 79 cents a share and revenue of $24.37 billion.

The results come a day after Exxon posted a 46% drop in first-quarter profit, also hurt by the sharp slump in oil prices, though its results topped expectations.